DLF Group was founded by Chaudhary Raghvendra Singh in 1946, not Karsanbhai Khodidas Patel (who founded Nirma). The other pairs are correctly matched: HCL was founded by Shiv Nadar, Ranbaxy by Bhai Mohan Singh, and Hero Group by Brijmohan Lal Munjal (BM Munjal). This question tests knowledge of Indian business founders.